Leveling-instrument for builders



(No Model.)

J. PAOLI. LEVELING INSTRUMENT FOR BUILDERS.

Patented Oct. 13, 1891.

of the King of Italy,

UNITED STATES PATENT OFFICE.

JOHN PAOLI, OF HOBOKEN, NEIV JERSEY.

LEVELlNG-INSTRUMENT FOR BUILDERS.

, SPECIFICATION forming part of Letters Patent No. 461,390, datedOctober 13, 1891.

Application filed March 1'7, 189.1 Serial No. 385,335. (No model.)

To all whom it may concern:

Be it known that I, JOHN PAOLI, a subjec residing in Hoboken, Hudsoncounty,

provement in Builders Levels, of which the following is a specification.

I have successfully introduced into the builders level provisions forallowing it to serve usefully in testing vertical lines and in measuringthe horizontal angles between oba long leveling-tube; and to attaingreater adjusted to serve as a transit.

refinem cut and convenience in accurate leveling than can be had withthe. necessarily shorter tubes in the transit instrument, I providemeans for changing the condition of a single telescope, so that it mayserve alternately at will in one adjustment as a level, with theordinary powers and accuracy of the builders level, and then, by achange in the conditions effected with little expenditure of labor andrequiring little skill, the same telescope is adapted to be inclinedupward and downward through a considerable range, and to determinevertical lines and to measure angles between objects at different levelswith an accuracy closely approximating that of the transit instrument.To attain this, the telescope is provided with long trunnions at rightangles to its axis, eachhaving a large hearing which matches in thesupports. In what I esteem the most complete means of carrying out theinvention these trunnions are removable, so that when the instrument isadjusted to serve as a level the trunnions will be not only out of use,but may be removed and stowed away until wanted.

The accompanying drawings form a part of this specification, andrepresent what I consider the best means of carrying out the invention.

Figure 1 is a side elevation showing the instrument adjusted forleveling. Fig. 2 is a corresponding side elevation with the parts Inthis view in the State of New Jersey, have invented a certain new anduseful Im- I the telescope has been lifted out of its bear- 7 ings andretained in the same direction as in Fig. 1, but inverted, so that thelevel is raised out of the way and has become ineffective. The partwhich supports the telescope,'corresponding to the alidade intheordinary t ran sit, has been turned at an angle of ninety degrees, sothat it is presented in end view. The telescope is supported through themedium of long trunnions with bearings exactly corresponding in diameterto the telescope, these large bearings resting in the alidade in thesponding parts in all the figures where they appear.

A is a telescope, adapted to rest by its cylindrical bearings A A in theforked supports B B, carried in a horizontal revolving body or alidadeD, which is capable of turning ona tapering central pivot in theordinary manner. (Not shown.) The telescope is locked into the forks B,respectively, by curved levers C, capable of being readily secured andreleased in the long-approved or in any other suitable manner.

E is a rigid yoke surrounding the body A, at or near the center ofgravity thereof, and having on each side an accurately-formed socket e,each having an internal screw-thread e and an accurately-formed conicalseat 6 G G are stout trunnions, each having a screw-threaded end G andan accuratelyformed conical shoulder G matching the conical seat e andadapted to bear very firmly and reliably thereon when the trunnion isscrewed home. Each trunnion has near its outer end a flange G and acylindrical bearing-surface G the diameter of which latter is the sameas that of the body of the telescope.

same manner as the telescope rested before on the exterior of the sleeve0, and adapted to be rotated thereon.

D is an arm carried on the alidade D and matching against the innerperiphery of the graduated ring T to allow the reading of the I angleaccurately. It will be understood that the telescope is provided withsuitable adjustments for the eye-piece, the cross-hairs, &c., that theforks B and the leveling-tube H are providedwith adjustments, and thatthe bottom plate W may be equipped with the refinements of support andadjustment common in instruments of this class.

When the instrument is used as a level, it serves in all respects in theordinary and longimproved manner. The instrument being leveled, thetelescope may be turned in any required position and the telescope maybe reversed and the alidade correspondingly reversed to reduce theerrors due to imperfections of the instrument. The long bearingsafforded by the instrument allow the accuracy of determination of levelfor which the ordinary builders level is greatly valued.

\Vhen it is desired to determine the vertical condition of a line, asthe wall of the building, or to attain any other desired ends whichrequire the telescope to be inclined, the following steps are taken:first, the trunnions are inserted in their sockets e and turned untilthey are firmly set, the construction assuring that the trunnions shallcome to rest exactly at right angles to the axis of the telescope. Thenthe levers 0 being detached the telescope is lifted out of its bearingsin the forks B, so that the leveling-tube H is presented on the upperinstead of the under side and swung horizontally, so that the bearings Gon the ends of the trunnions G rest in the forks B and the levers G arebrought down upon the trunnion-bearings and locked. Now the telescope isfree to rock on its bearings, so that it may sight an object at aconsiderable angle above or below the horizontal. Now directing thetelescope to any portion, as the corner of a building, and locking thealidade in that posit-ion, the line of sight of the telescope may betraversed up and down the line and its correctness determined with greataccuracy. The positions of windows or other points which should comedirectly over each other can be now determined with fineness.

When it is desired by this instrument to measure the extent of thehorizontal angle beels with it.

tween two objects in the same level or at different levels, thegraduated ring T is brought into-use. It is turned so that O or anyother graduation coincides with the line of the telescope when directedtoward one of the ob ects and locked, the telescope being then turneduntil it ranges at the other object, the alidade D, and consequently theVernier-arm D, trav- When the second position has been accuratelyattained, the angle may be read off from the graduated circle in the0bvious manner.

The yoke E is made in two halves secured together by screws E, the upperpart be ng the larger, and the two when properly applied togetherloosely embracing the tube A of the telescope, so that there is room forad ustment. The upper and main part of the yoke has short arms E on eachside, extending longitudinally of the telescope. Through each of thesearms are tapped ad ustingscrews F, which are set against the body of thetube A. By changing the adjustment of these screws the position of theyoke E, .and consequently of the trunnions G, may be changed. Thisallows the trunnions to be adjusted to secure and maintain theirposition exactly at right angles to the axis of the telescope.

Modifications may be made without departing from the principle orsacrificing the advantages of the invention. I have shown two stops Dfitted on the alidade (see Figs. 1 and 2) in the positions to arrest thetelescope when it has been elevated or depressed to the extentallowable. the instrument is used with sufficient care.

When the angle at which the telescope is to be inclined is very little,the telescope may be mounted by its trunnions in the manner describedand used without being inverted. In possible cases this may be anadvantage by allowing the leveling-tube to perform its usual functionsand the instrument be used, if required, as a level for a'brief periodwithout changing the adjustment.

I claim as an improvement in builders levels 1. The telescope A,provided with long trunnions having bearings G adapted to engage in thesame forks as the telescope, in combination with each other and with theforks B and alidade D, adapted to allow the instrument to be used atwill as a level or as a transit, as herein specified.

2. In a builders level, the long trunnions G G made independent of thetelescope and having screw-threads G, and accurately-finished shouldersG in combination with the telescope A, having firmlyfixed sockets 6,each with a hollow screw-thread e and accurately-finished seat 6 adaptedto be applied and removed as herein specified.

3. 1n a builders level, the alidade D, forks B, telescope A, and longtrunnions G, having bearings G at their ends, in combination These maybe omitted if with each other and with the yoke E, loosely above setforth I affix my signature in presinclosing the telescope and. providedwith ence of two witnesses. sockets e and arms E and with theadjusting-sorews F, tapped through such arms and v I JOHN PAOLI' 5engaging with the telescope, as herein speci- Witnesses: r

fled. SUsAN B. PAOLI,

In testimony that I claim the invention JOHN WHITE.

